1. Biology, 9th ed,Sylvia Mader
Chapter 04
Cell Structure and Function
Chapter 4: pp
Cell Structure and Function
Plasma membrane:
outer surface that
regulates entrance and exit of molecules
Ribosome:
site of protein synthesis
Fimbriae:
hairlike bristles that
allow adhesion to
the surfaces
Inclusion body:
stored nutrients for
later use
Conjugation pilus:
elongated, hollow
appendage used for
DNA transfer to other
bacterial cells
Mesosome:
plasma membrane
that folds into the
cytoplasm and
increases surface area
Nucleus:
Cytoskeleton: maintains cell shape and assists movement of cell parts:
Nucleoid:
location of the bacterial
chromosome
Plasma membrane:
sheath around cytoplasm
that regulates entrance
and exit of molecules
Endoplasmic reticulum:
Cell wall:
covering that supports,
shapes, and protects cell
Glycocalyx:
gel-like coating outside
cell wall; if compact, called
a capsule; if diffuse, called
a slime layer
Flagellum:
rotating filament present
in some bacteria that
pushes the cell forward
*not in plant cells

2. Biology, 9th ed,Sylvia Mader
Chapter 04
Outline
Cell Structure and Function
Cellular Level of Organization
Cell theory
Cell size
Prokaryotic Cells
Eukaryotic Cells
Organelles
Nucleus and Ribosome
Endomembrane System
Other Vesicles and Vacuoles
Energy related organelles
Cytoskeleton
Centrioles, Cilia, and Flagella

3. Biology, 9th ed,Sylvia Mader
Chapter 04
Cell Theory
Cell Structure and Function
Detailed study of the cell began in the 1830s
A unifying concept in biology
Originated from the work of biologists Schleiden and Schwann in
States that:
All organisms are composed of cells
German botanist Matthais Schleiden in 1838
German zoologist Theodor Schwann in 1839
All cells come only from preexisting cells
German physician Rudolph Virchow in 1850’s
Cells are the smallest structural and functional unit of organisms

4. Biology, 9th ed,Sylvia Mader
Chapter 04
Organisms and Cells
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. a. c. b. 50 m d.
140 m
a: © Geoff Bryant/Photo Researchers, Inc.; b: Courtesy Ray F. Evert/University of Wisconsin Madison; c: © Barbara J. Miller/Biological Photo Service; d: Courtesy O. Sabatakou and E. Xylouri-Frangiadak

5. Biology, 9th ed,Sylvia Mader
Chapter 04
Sizes of Living Things
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
0.1 nm
1 nm
10 nm
100 nm 1 m 10 m
100 m
1 mm
1 cm
0.1 m
1 m
10 m
100 m
1 km
protein
chloroplast
plant and
animal
cells
mouse
rose
frog egg
amino
acid
virus
ostrich
egg
most bacteria
human egg
ant
atom
blue whale
human
electron microscope
light microscope
human eye

6. Biology, 9th ed,Sylvia Mader
Chapter 04
Cell Size
Cell Structure and Function
Cells range in size from one millimeter down to one micrometer
Cells need a large surface area of plasma membrane to adequately exchange materials.
The surface‑area‑to‑volume ratio requires that cells be small
Large cells - surface area relative to volume decreases
Volume is living cytoplasm, which demands nutrients and produces wastes
Cells specialized in absorption utilize membrane modifications such as microvilli to greatly increase surface area per unit volume

7. Surface to Volume Ratio
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
One 4-cm cube
Eight 2-cm cubes
Sixty-four 1-cm cubes
Total surface area (height × width × number of sides × number of cubes)
96 cm2
192 cm2
384 cm2
Total volume (height × width × length × number of cubes)
64 cm3
64 cm3
64 cm3
Surface area: Volume per cube (surface area ÷ volume)
1.5:1
3:1
6:1

8. Microscopy Today: Compound Light Microscope
Biology, 9th ed,Sylvia Mader
Chapter 04
Microscopy Today: Compound Light Microscope
Cell Structure and Function
Light passed through specimen
Focused by glass lenses
Image formed on human retina
Max magnification about 1000X
Resolves objects separated by 0.2 mm, 500X better than human eye

9. Compound Light Microscope
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 85 m
amoeba, light micrograph
eye
ocular lens
light rays
objective lens
specimen
condenser lens
light source
a. Compound light microscope
© Robert Brons/Biological Photo Service

10. Microscopy Today: Transmission Electron Microscope
Biology, 9th ed,Sylvia Mader
Chapter 04
Microscopy Today: Transmission Electron Microscope
Cell Structure and Function
Abbreviated T.E.M.
Electrons passed through specimen
Focused by magnetic lenses
Image formed on fluorescent screen
Similar to TV screen
Image is then photographed
Max magnification 1000,000sX
Resolves objects separated by mm, 100,000X better than human eye

11. Transmission Electron Microscope
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
200 nm
pseudopod segment, transmission electron
micrograph
electron source
electron beam
electromagnetic
condenser lens
specimen
electromagnetic
objective lens
electromagnetic
projector lens
observation screen or
photographic plate
b. Transmission electron microscope
© M. Schliwa/Visuals Unlimited

12. Microscopy Today: Scanning Electron Microscope
Biology, 9th ed,Sylvia Mader
Chapter 04
Microscopy Today: Scanning Electron Microscope
Cell Structure and Function
Abbreviated S.E.M.
Specimen sprayed with thin coat of metal
Electron beam scanned across surface of specimen
Metal emits secondary electrons
Emitted electrons focused by magnetic lenses
Image formed on fluorescent screen
Similar to TV screen
Image is then photographed

13. Scanning Electron Microscope
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
500 m
amoeba, scanning electron micrograph
electron gun
electron beam
electromagnetic
condenser
lenses
scanning coil
final
condenser
electron
lens
detector
secondary
electrons TV
specimen
viewing
screen
c. Scanning electron microscope
© Kessel/Shih/Peter Arnold, Inc.

14. Microscopy Today: Immunofluorescence Light Microscope
Biology, 9th ed,Sylvia Mader
Chapter 04
Microscopy Today: Immunofluorescence Light Microscope
Cell Structure and Function
Antibodies developed against a specific protein
Fluorescent dye molecule attached to antibody molecules
Specimen exposed to fluorescent antibodies
Ultra-violet light (black light) passed through specimen
Fluorescent dye glows in color where antigen is located
Emitted light is focused by glass lenses onto human retina
Allows mapping distribution of a specific protein in cell

15. Microscopy Today: Confocal Microscopy
Biology, 9th ed,Sylvia Mader
Chapter 04
Microscopy Today: Confocal Microscopy
Cell Structure and Function
Narrow laser beam scanned across transparent specimen
Beam is focused at a very thin plane
Allows microscopist to optically section a specimen
Sections made at different levels
Allows assembly of 3d image on computer screen that can be rotated

16. Microscopy and Amoeba proteus
Biology, 9th ed,Sylvia Mader
Chapter 04
Microscopy and Amoeba proteus
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 85 m
200 nm
500 m
amoeba, light micrograph
pseudopod segment, transmission electron
micrograph
amoeba, scanning electron micrograph
electron source
electron gun
eye
electron beam
ocular lens
electron beam
light rays
electromagnetic
condenser lens
electromagnetic
condenserl
enses
specimen
electromagnetic
objective lens
objective lens
scanning coil
specimen
condenser lens
final
Condenser
lens
electromagnetic
projector lens
electron detector
secondary
electrons
observation screen or
photographic plate TV
Viewing
screen
specimen
light source
a. Compound light microscope b. T
ransmission electron microscope
c. Scanning electron microscope
a: © Robert Brons/Biological Photo Service; b: © M. Schliwa/Visuals Unlimited; c: © Kessel/Shih/Peter Arnold, Inc.

17. Microscopy and Cheek Cells
Biology, 9th ed,Sylvia Mader
Chapter 04
Microscopy and Cheek Cells
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 30 m 30 m 25 m 25 m 25 m
Bright-field. Light
passing through the
specimen is brought
directly into focus. Usually,
the low level of contrast
within the specimen
interferes with viewing all
but its largest components.
Bright-field (stained).
Dyes are used to stain
the specimen. Certain
components take up
the dye more than other
components, and therefore
contrast is enhanced.
Differential interference
contrast. Optical methods
are used to enhance
density differences within
the specimen so that
certain regions appear
brighter than others. This
technique is used to view
living cells, chromosomes,
and organelle masses.
Phase contrast. Density
differences in the
specimen cause light rays
to come out of “phase.”
The microscope enhances
these phase differences so
that some regions of the
specimen appear brighter
or darker than others. The
technique is widely used
to observe living cells and
organelles.
Dark-field. Light is passed
through the specimen at
an oblique angle so that
the objective lens receives
only light diffracted and
scattered by the object.
This technique is used to
view organelles, which
appear quite bright against
a dark field.
(Bright field): © Ed Reschke; (Bright field stained): © Biophoto Associates/Photo Researchers, Inc.; (Differential, Phase contrast, Dark field): © David M. Phillips/Visuals Unlimited

18. Biology, 9th ed,Sylvia Mader
Chapter 04
Prokaryotic Cells
Cell Structure and Function
Lack a membrane-bound nucleus
Structurally smaller and simpler than eukaryotic cells (which have a nucleus).
Prokaryotic cells are placed in two taxonomic domains:
Bacteria
Archaea
Live in extreme habitats
Domains are structurally similar but biochemically different

19. The Structure of Bacteria
Extremely small - 1–1.5 μm wide and 2–6 μm long
Occur in three basic shapes:
Spherical coccus,
Rod-shaped bacillus,
Spiral spirillum (if rigid) or spirochete (if flexible).
Cell Envelope includes:
Plasma membrane - lipid bilayer with imbedded and peripheral protein
Form internal pouches (mesosomes)
Cell wall - maintains the shape of the cell and is strengthened by peptidoglycan
Glycocalyx - layer of polysaccharides on the outside of the cell wall
Well organized and resistant to removal (capsule)

20. The Structure of Bacteria
Biology, 9th ed,Sylvia Mader
Chapter 04
The Structure of Bacteria
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
spirillum
spirochete
bacillus
coccus

21. The Structure of Bacteria
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
protein molecules
phospholipid bilayer

22. The Structure of Bacteria
Biology, 9th ed,Sylvia Mader
Chapter 04
The Structure of Bacteria
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Ribosome:
site of protein synthesis
Fimbriae:
hairlike bristles that
allow adhesion to
the surfaces
Inclusion body:
stored nutrients for
later use
Conjugation pilus:
elongated, hollow
appendage used for
DNA transfer to other
bacterial cells
Mesosome:
plasma membrane
that folds into the
cytoplasm and
increases surface area
Nucleoid:
location of the bacterial
chromosome
Plasma membrane:
sheath around cytoplasm
that regulates entrance
and exit of molecules
Cell wall:
covering that supports,
shapes, and protects cell
Glycocalyx:
gel-like coating outside
cell wall; if compact, called
a capsule; if diffuse, called
a slime layer
Flagellum:
rotating filament present
in some bacteria that
pushes the cell forward
Escherichia coli
© Howard Sochurek/The Medical File/Peter Arnold, Inc.

23. The Structure of Bacteria Cytoplasm & Appendages
Biology, 9th ed,Sylvia Mader
Chapter 04
The Structure of Bacteria Cytoplasm & Appendages
Cell Structure and Function
Cytoplasm
Semifluid solution
Bounded by plasma membrane
Contains water, inorganic and organic molecules, and enzymes.
Nucleoid is a region that contains the single, circular DNA molecule.
Plasmids are small accessory (extrachromosomal) rings of DNA
Appendages
Flagella – Provide motility
Fimbriae – small, bristle-like fibers that sprout from the cell surface
Sex pili – rigid tubular structures used to pass DNA from cell to cell

24. Biology, 9th ed,Sylvia Mader
Chapter 04
Eukaryotic Cells
Cell Structure and Function
Domain Eukarya includes:
Protists
Fungi
Plants
Animals
Cells contain:
Membrane-bound nucleus that houses DNA
Specialized organelles
Plasma membrane
Much larger than prokaryotic cells
Some cells (e.g., plant cells) have a cell wall

25. Hypothesized Origin of Eukaryotic Cells
Biology, 9th ed,Sylvia Mader
Chapter 04
Hypothesized Origin of Eukaryotic Cells
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Original
prokaryotic cell
DNA
1. Cell gains a nucleus by the
plasma membrane invaginating
and surrounding the DNA
with a double membrane.
2. Cell gains an endomembrane
system by proliferation
of membrane.
3. Cell gains mitochondria.
aerobic
bacterium
mitochondrion
4. Cell gains chloroplasts.
chloroplast
photosynthetic
bacterium
Animal cell
has mitochondria,
but not chloroplasts.
Plant cell
has both mitochondria
and chloroplasts.

26. Eukaryotic Cells: Organelles
Biology, 9th ed,Sylvia Mader
Chapter 04
Eukaryotic Cells: Organelles
Cell Structure and Function
Eukaryotic cells are compartmentalized
They contain small structures called organelles
Perform specific functions
Isolates reactions from others
Two classes of organelles:
Endomembrane system:
Organelles that communicate with one another
Via membrane channels
Via small vesicles
Energy related organelles
Mitochondria & chloroplasts
Basically independent & self-sufficient

27. Biology, 9th ed,Sylvia Mader
Chapter 04
Plasma Membrane
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
protein molecules
phospholipid bilayer

28. Cell Fractionation and Differential Centrifugation
Biology, 9th ed,Sylvia Mader
Chapter 04
Cell Fractionation and Differential Centrifugation
Cell Structure and Function
Cell fractionation is the breaking apart of cellular components
Differential centrifugation:
Allows separation of cell parts
Separated out by size & density
Works like spin cycle of washer
The faster the machine spins, the smaller the parts that are settled out

29. Cell Fractionation and Differential Centrifugation
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Grind cells
Centrifuge cells at
different speeds
speed of 600 g
for 10 min
speed of 15,000 g
for 5 min
speed of 100,000 g
for 60 min
soluble portion
of cytoplasm
nuclei
in sediment
mitochondria and lysosomes
in sediment
ribosomes and endoplasmic
reticulum in sediment

30. Biology, 9th ed,Sylvia Mader
Chapter 04
Animal Cell Anatomy
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Plasma membrane:
outer surface that
regulates entrance and
exit of molecules
protein
phospholipid
Nucleus: command center of cell
Nuclear envelope: double membrane with nuclear pores that encloses nucleus
Cytoskeleton: maintains
cell shape and assists movement
of cell parts:
Chromatin: diffuse threads
containing DNA and protein
Microtubules: protein
cylinders that move organelles
Nucleolus: region that produces
subunits of ribosomes
Endoplasmic reticulum:
protein and lipid metabolism
Intermediate filaments:
protein fibers that provide stability of shape
Rough ER: studded with ribosomes that synthesize proteins
Actin filaments: protein
fibers that play a role in change of shape
Smooth ER: lacks ribosomes, synthesizes
lipid molecules
Centrioles*: short
cylinders of microtubules
of unknown function
Peroxisome: vesicle that is involved in fatty acid metabolism
Centrosome: microtubule
organizing center that
contains a pair of centrioles
Ribosomes: particles that carry
out protein synthesis
Lysosome*: vesicle that
digests macromolecules
and even cell parts
Polyribosome: string of ribosomes simultaneously
synthesizing same protein
Vesicle: small membrane- bounded sac that stores and transports substances
Mitochondrion: organelle that carries out cellular respiration, producing ATP molecules
Cytoplasm: semifluid matrix outside nucleus that contains organelles
Golgi apparatus: processes, packages,
and secretes modified proteins
*not in plant cells

31. Biology, 9th ed,Sylvia Mader
Chapter 04
Plant Cell Anatomy
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Nucleus: command center of cell
Central vacuole*: large, fluid-filled
sac that stores metabolites and
helps maintain turgor pressure
Nuclear envelope: double membrane with
nuclear pores that encloses nucleus
Nucleolus: produces subunits of ribosomes
Chromatin: diffuse threads containing
DNA and protein
Cell wall of adjacent cell
Nuclear pore: permits passage of
proteins into nucleus and ribosomal
subunits out of nucleus
Middle lamella:
cements together the
primary cell walls of
adjacent plant cells
Ribosomes: carry
out protein synthesis
Chloroplast*: carries
out photosynthesis,
producing sugars
Centrosome:
microtubule organizing
center (lacks centrioles)
Granum*: a stack
of chlorophyll-containing
thylakoids
in a chloroplast
Endoplasmic
reticulum: protein
and lipid metabolism
Rough ER: studded
with ribosomes that
synthesize proteins
Mitochondrion: organelle
that carries out cellular
respiration, producing
ATP molecules
Smooth ER: lacks
ribosomes, synthesizes
lipid molecules
Microtubules: protein cylinders
that aid movement of organelles
Peroxisome: vesicle that
is involved in fatty acid
metabolism
Actin filaments: protein fibers
that play a role in movement of
cell and organelles
Golgi apparatus: processes,
packages, and secretes
modified proteins
Plasma membrane: surrounds
cytoplasm, and regulates entrance
and exit of molecules
Cytoplasm: semifluid matrix outside
nucleus that contains organelles
Cell wall*: outer surface that shapes,
supports, and protects cell
*not in animal cells

32. Biology, 9th ed,Sylvia Mader
Chapter 04
Nucleus
Cell Structure and Function
Command center of cell, usually near center
Separated from cytoplasm by nuclear envelope
Consists of double layer of membrane
Nuclear pores permit exchange between nucleoplasm & cytoplasm
Contains chromatin in semifluid nucleoplasm
Chromatin contains DNA of genes, and proteins
Condenses to form chromosomes
Chromosomes are formed during cell division
Dark nucleolus composed of rRNA
Produces subunits of ribosomes

33. Biology, 9th ed,Sylvia Mader
Chapter 04
Anatomy of the Nucleus
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
nuclear
envelope
nucleolus
Nuclear envelope:
nuclear
inner membrane
pore
outer membrane
chromatin
nucleoplasm
nuclear pore
phospholipid
(Bottom): Courtesy Ron Milligan/Scripps Research Institute; (Top right): Courtesy E.G. Pollock

34. Biology, 9th ed,Sylvia Mader
Chapter 04
Ribosomes
Cell Structure and Function
Are the site of protein synthesis in the cell
Composed of rRNA
Consists of a large subunit and a small subunit
Subunits made in nucleolus
May be located:
On the endoplasmic reticulum (thereby making it “rough”), or
Free in the cytoplasm, either singly or in groups, called polyribosomes

35. Biology, 9th ed,Sylvia Mader
Chapter 04
Nucleus, Ribosomes, & ER
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Cytoplasm
Endoplasmic
reticulum (ER)
protein
ER membrane
4. An enzyme removes
the signal peptide.
Lumen of ER
5. Ribosomal subunits and
mRNA break away. The
protein remains in the ER
and folds into its final shape.
enzyme
mRNA
receptor
SRP
signal recognition particle (SRP)
2. Signal recognition
particle (SRP) binds
to signal peptide.
3. SRP attaches to receptor (purple);
a channel opens; and the
polypeptide enters ER..
signal peptide
ribosomal subunits
ribosome
nuclear pore
mRNA
mRNA
DNA
1. mRNA is leaving the
nucleus and is attached
to the ribosome; protein
synthesis is occurring.
Nucleus

36. Biology, 9th ed,Sylvia Mader
Chapter 04
Endomembrane System
Cell Structure and Function
Series of intracellular membranes that compartmentalize the cell
Restrict enzymatic reactions to specific compartments within cell
Consists of:
Nuclear envelope
Membranes of endoplasmic reticulum
Golgi apparatus
Vesicles
Several types
Transport materials between organelles of system

37. Endomembrane System: The Endoplasmic Reticulum
Biology, 9th ed,Sylvia Mader
Chapter 04
Endomembrane System: The Endoplasmic Reticulum
Cell Structure and Function
A system of membrane channels and saccules (flattened vesicles) continuous with the outer membrane of the nuclear envelope
Rough ER
Studded with ribosomes on cytoplasmic side
Protein anabolism
Synthesizes proteins
Modifies and processes proteins
Adds sugar to protein
Results in glycoproteins
Smooth ER
No ribosomes
Synthesis of lipids
Site of various synthetic processes, detoxification, and storage
Forms transport vesicles

38. Endoplasmic Reticulum
Biology, 9th ed,Sylvia Mader
Chapter 04
Endoplasmic Reticulum
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
ribosomes
nuclear envelope
rough
endoplasmic
reticulum
smooth
endoplasmic
reticulum
0.08 m
© R. Bolender & D. Fawcett/Visuals Unlimited

39. Endomembrane System: The Golgi Apparatus
Biology, 9th ed,Sylvia Mader
Chapter 04
Endomembrane System: The Golgi Apparatus
Cell Structure and Function
Golgi Apparatus
Consists of 3-20 flattened, curved saccules
Resembles stack of hollow pancakes
Modifies proteins and lipids
Receives vesicles from ER on cis (or inner face)
Packages them in vesicles
Prepares for “shipment” in v Packages them in vesicles from trans (or outer face)
Within cell
Export from cell (secretion, exocytosis)

40. Biology, 9th ed,Sylvia Mader
Chapter 04
Golgi Apparatus
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
secretion
transport
vesicle
saccules
transport
vesicle
trans face
cis face
Golgi apparatus
Nucleus
0.1 m
Courtesy Charles Flickinger, from Journal of Cell Biology 49: , 1971, Fig. 1 page 224

41. Endomembrane System: Lysosomes
Biology, 9th ed,Sylvia Mader
Chapter 04
Endomembrane System: Lysosomes
Cell Structure and Function
Membrane-bound vesicles (not in plants)
Produced by the Golgi apparatus
Contain powerful digestive enzymes and are highly acidic
Digestion of large molecules
Recycling of cellular resources
Apoptosis (programmed cell death, like tadpole losing tail)
Some genetic diseases
Caused by defect in lysosomal enzyme
Lysosomal storage diseases (Tay-Sachs)

42. Biology, 9th ed,Sylvia Mader
Chapter 04
Lysosomes
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
lysosome
mitochondrion
peroxisome fragment
a. Mitochondrion and a peroxisome in a lysosome
b. Storage bodies in a cell with defective lysosomes
a: Courtesy Daniel S. Friend; b: Courtesy Robert D. Terry/Univ. of San Diego School of Medicine

43. Animation
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44. Endomembrane System: Summary
Proteins produced in rough ER and lipids from smooth ER are carried in vesicles to the Golgi apparatus.
The Golgi apparatus modifies these products and then sorts and packages them into vesicles that go to various cell destinations.
Secretory vesicles carry products to the membrane where exocytosis produces secretions.
Lysosomes fuse with incoming vesicles and digest macromolecules.

45. Endomembrane System: A Visual Summary
Biology, 9th ed,Sylvia Mader
Chapter 04
Endomembrane System: A Visual Summary
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
secretion
plasma
membrane
incoming vesicle
brings substances into the
cell that are digested when
the vesicle fuses with a
lysosome
secretory vesicle
fuses with the plasma
membrane as secretion
occurs
enzyme
Golgi apparatus
modifies lipids and proteins
from the ER; sorts them
and packages them in
vesicles
lysosome
contains digestive enzymes
that break down worn-out
cell parts or substances
entering the cell at the
plasma membrane
protein
transport vesicle
shuttles proteins to
various locations such as
the Golgi apparatus
transport vesicle
shuttles lipids to various
locations such as the
Golgi apparatus
lipid
rough endoplasmic
reticulum
synthesizes proteins and
packages them in vesicles;
vesicles commonly go to
the Golgi apparatus
smooth endoplasmic
reticulum
synthesizes lipids and
also performs various
other functions
ribosome
Nucleus

46. Biology, 9th ed,Sylvia Mader
Chapter 04
Peroxisomes
Cell Structure and Function
Similar to lysosomes
Membrane-bounded vesicles
Enclose enzymes
However
Enzymes synthesized by free ribosomes in cytoplasm (instead of ER)
Active in lipid metabolism
Catalyze reactions that produce hydrogen peroxide H2O2
Toxic
Broken down to water & O2 by catalase

47. Biology, 9th ed,Sylvia Mader
Chapter 04
Peroxisomes
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
100 nm
© S.E. Frederick & E.H. Newcomb/Biological Photo Service

48. Biology, 9th ed,Sylvia Mader
Chapter 04
Vacuoles
Cell Structure and Function
Membranous sacs that are larger than vesicles
Store materials that occur in excess
Others very specialized (contractile vacuole)
Plants cells typically have a central vacuole
Up to 90% volume of some cells
Functions in:
Storage of water, nutrients, pigments, and waste products
Development of turgor pressure
Some functions performed by lysosomes in other eukaryotes

49. Biology, 9th ed,Sylvia Mader
Chapter 04
Vacuoles
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
100 nm
© Newcomb/Wergin/Biological Photo Service

50. Energy-Related Organelles: Chloroplast Structure
Biology, 9th ed,Sylvia Mader
Chapter 04
Energy-Related Organelles: Chloroplast Structure
Cell Structure and Function
Bounded by double membrane
Inner membrane infolded
Forms disc-like thylakoids, which are stacked to form grana
Suspended in semi-fluid stroma
Green due to chlorophyll
Green photosynthetic pigment
Found ONLY in inner membranes of chloroplast

51. Energy-Related Organelles: Chloroplasts
Biology, 9th ed,Sylvia Mader
Chapter 04
Energy-Related Organelles: Chloroplasts
Cell Structure and Function
Membranous organelles (a type of plastid) that serve as the site of photosynthesis
Captures light energy to drive cellular machinery
Photosynthesis
Synthesizes carbohydrates from CO2 & H2O
Makes own food using CO2 as only carbon source
Energy-poor compounds converted to energy-rich compounds
solar energy + carbon dioxide + water → carbohydrate + oxygen
Only plants, algae, and certain bacteria are capable of conducting photosynthesis

52. Energy-Related Organelles: Chloroplasts
Bound by a double membrane organized into flattened disc-like sacs called thylakoids
Chlorophyll and other pigments capture solar energy
Enzymes synthesize carbohydrates

53. Chloroplast Structure
Biology, 9th ed,Sylvia Mader
Chapter 04
Chloroplast Structure
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. a.
500 nm
outer
membrane
thylakoid
space
grana
stroma
thylakoid membrane
double
membrane
inner
membrane b.
a: Courtesy Herbert W. Israel, Cornell University

54. Energy-Related Organelles: Mitochondria
Biology, 9th ed,Sylvia Mader
Chapter 04
Energy-Related Organelles: Mitochondria
Cell Structure and Function
Smaller than chloroplast
Contain ribosomes and their own DNA
Surrounded by a double membrane
Inner membrane surrounds the matrix and is convoluted (folds) to form cristae.
Matrix – Inner semifluid containing respiratory enzymes
Break down carbohydrates
Involved in cellular respiration
Produce most of ATP utilized by the cell

55. Mitochondrial Structure
Biology, 9th ed,Sylvia Mader
Chapter 04
Mitochondrial Structure
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. a.
200 nm
outer
membrane
cristae
matrix
double
membrane
inner
membrane b.
a: Courtesy Dr. Keith Porter

56. Biology, 9th ed,Sylvia Mader
Chapter 04
The Cytoskeleton
Cell Structure and Function
Maintains cell shape
Assists in movement of cell and organelles
Three types of macromolecular fibers
Actin Filaments
Intermediate Filaments
Microtubules
Assemble and disassemble as needed

57. The Cytoskeleton: Actin Filaments
Biology, 9th ed,Sylvia Mader
Chapter 04
The Cytoskeleton: Actin Filaments
Cell Structure and Function
Extremely thin filaments like twisted pearl necklace
Dense web just under plasma membrane maintains cell shape
Support for microvilli in intestinal cells
Intracellular traffic control
For moving stuff around within cell
Cytoplasmic streaming
Function in pseudopods of amoeboid cells
Pinch mother cell in two after animal mitosis
Important component in muscle contraction (other is myosin)

58. The Cytoskeleton: Actin Filament Operation
Biology, 9th ed,Sylvia Mader
Chapter 04
The Cytoskeleton: Actin Filament Operation
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
actin filament
ATP
ADP + P
myosin
molecules
tail
head
membrane

59. The Cytoskeleton: Intermediate Filaments
Biology, 9th ed,Sylvia Mader
Chapter 04
The Cytoskeleton: Intermediate Filaments
Cell Structure and Function
Intermediate in size between actin filaments and microtubules
Rope-like assembly of fibrous polypeptides
Vary in nature
From tissue to tissue
From time to time
Functions:
Support nuclear envelope
Cell-cell junctions, like those holding skin cells tightly together

60. The Cytoskeleton: Microtubules
Biology, 9th ed,Sylvia Mader
Chapter 04
The Cytoskeleton: Microtubules
Cell Structure and Function
Hollow cylinders made of two globular proteins called a and b tubulin
Spontaneous pairing of a and b tubulin molecules form structures called dimers
Dimers then arrange themselves into tubular spirals of 13 dimers around
Assembly:
Under control of Microtubule Organizing Center (MTOC)
Most important MTOC is centrosome
Interacts with proteins kinesin and dynein to cause movement of organelles

61. The Cytoskeleton: Microtubule Operation
Biology, 9th ed,Sylvia Mader
Chapter 04
The Cytoskeleton: Microtubule Operation
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
ATP
vesicle
kinesin receptor
kinesin
vesicle moves, not microtubule

62. The Cytoskeleton actin subunit Chara a. Actin filaments fibrous
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
actin
subunit
Chara
a. Actin filaments
fibrous
subunits
peacock
b. Intermediate filaments
tubulin
dimer
chameleon
c. Microtubules
a(Actin): © M. Schliwa/Visuals Unlimited; b, c(Intermediate, Microtubules): © K.G. Murti/Visuals Unlimited; a(Chara): The McGraw-Hill Companies, Inc./photo by Dennis Strete and Darrell Vodopich; b(Peacock): © Vol. 86/Corbis; c(Chameleon): © Photodisc/Vol. 6/Getty Images

63. Microtubular Arrays: Centrioles
Biology, 9th ed,Sylvia Mader
Chapter 04
Microtubular Arrays: Centrioles
Cell Structure and Function
Short, hollow cylinders
Composed of 27 microtubules
Microtubules arranged into 9 overlapping triplets
One pair per animal cell
Located in centrosome of animal cells
Oriented at right angles to each other
Separate during mitosis to determine plane of division
May give rise to basal bodies of cilia and flagella

64. Cytoskeleton: Centrioles
Biology, 9th ed,Sylvia Mader
Chapter 04
Cytoskeleton: Centrioles
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
empty center
of centriole
one microtubule
triplet
one centrosome: one pair of centrioles
two centrosomes: two pairs of centrioles
200 nm
(Middle): Courtesy Kent McDonald, University of Colorado Boulder; (Bottom): Journal of Structural Biology, Online by Manley McGill et al. Copyright 1976 by Elsevier Science & Technology Journals. Reproduced with permission of Elsevier Science & Technology Journals in the format Textbook via Copyright Clearance Center

65. Microtubular Arrays: Cilia and Flagella
Biology, 9th ed,Sylvia Mader
Chapter 04
Microtubular Arrays: Cilia and Flagella
Cell Structure and Function
Hair-like projections from cell surface that aid in cell movement
Very different from prokaryote flagella
Outer covering of plasma membrane
Inside this is a cylinder of 18 microtubules arranged in 9 pairs
In center are two single microtubules
This pattern used by all cilia & flagella
In eukaryotes, cilia are much shorter than flagella
Cilia move in coordinated waves like oars
Flagella move like a propeller or cork screw

66. Structure of a Flagellum
Biology, 9th ed,Sylvia Mader
Chapter 04
Structure of a Flagellum
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
outer
microtubule
doublet
Flagellum
radial
spoke
central
microtubules
shaft
The shaft of the
flagellum has a ring
of nine microtubule
doublets anchored
to a central pair of
microtubules.
dynein
side arm
Flagellum cross section
25 nm
The side arms
of each doublet
are composed
of dynein, a
motor molecule.
dynein
side arms
Sperm
plasma
membrane
triplets
Basal body
ATP
In the presence of
ATP, the dynein side
arms reach out to
their neighbors,
and bending occurs.
The basal body of a flagellum has
a ring of nine microtubule triplets
with no central microtubules.
Basal body cross section
100 nm
(Flagellum, Basal body): © William L. Dentler/Biological Photo Service

67. Comparison of Prokaryotic and Eukaryotic Cells

68. Biology, 9th ed,Sylvia Mader
Chapter 04
Review
Cell Structure and Function
Cellular Level of Organization
Cell theory
Cell size
Prokaryotic Cells
Eukaryotic Cells
Organelles
Nucleus and Ribosome
Endomembrane System
Other Vesicles and Vacuoles
Energy related organelles
Cytoskeleton
Centrioles, Cilia, and Flagella

69. Biology, 9th ed,Sylvia Mader
Chapter 04
Cell Structure and Function
Chapter 4: pp
Cell Structure and Function
Plasma membrane:
outer surface that
regulates entrance and exit of molecules
Ribosome:
site of protein synthesis
Fimbriae:
hairlike bristles that
allow adhesion to
the surfaces
Inclusion body:
stored nutrients for
later use
Conjugation pilus:
elongated, hollow
appendage used for
DNA transfer to other
bacterial cells
Mesosome:
plasma membrane
that folds into the
cytoplasm and
increases surface area
Nucleus:
Cytoskeleton: maintains cell shape and assists movement of cell parts:
Nucleoid:
location of the bacterial
chromosome
Plasma membrane:
sheath around cytoplasm
that regulates entrance
and exit of molecules
Endoplasmic reticulum:
Cell wall:
covering that supports,
shapes, and protects cell
Glycocalyx:
gel-like coating outside
cell wall; if compact, called
a capsule; if diffuse, called
a slime layer
Flagellum:
rotating filament present
in some bacteria that
pushes the cell forward
*not in plant cells